Consolidated Statement of Stockholders Equity - USD ($) $ in Thousands	Total	Directors	Common Stock ($0.01 par value)	Additional Paid-in Capital	Additional Paid-in Capital Directors	Retained Earnings	Accumulated Other Comprehensive Loss
Opening Balance at Mar. 31, 2015	$ 268,719		$ 200	$ 203,156		$ 157,811	$ (92,448)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	19,579		0	0		19,579	0
Payments of Dividends	(3,217)		0	0		(3,217)	0
Change in foreign currency translation adjustment	3,650		0	0		0	3,650
Change in net unrealized gain on investments, net of tax	(233)		0	0		0	(233)
Change in derivatives qualifying as hedges, net of tax	(1,031)		0	0		0	(1,031)
Change in pension liability and postretirement obligations, net of tax	(4,685)		0	0		0	(4,685)
Stock compensation - directors	3,623	$ 440	0	3,623	$ 440	0	0
Stock Issued During Period, Value, Stock Options Exercised	243		1	242		0	0
Tax effect of exercise of stock options	118			118			0
Earned ESOP shares			0	(10)		0	0
Stock Repurchased and Retired During Period, Value	(10)
Restricted stock units released, shares, net of shares withheld for minimum statutory tax obligation	(887)		0	(887)		0	0
closing balance at Mar. 31, 2016	286,309		201	206,682		174,173	(94,747)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	8,984		0	0		8,984	0
Payments of Dividends	(3,422)		0	0		(3,422)	0
Change in foreign currency translation adjustment	(9,379)		0	0		0	(9,379)
Change in net unrealized gain on investments, net of tax	68		0	0		0	68
Change in derivatives qualifying as hedges, net of tax	(3,514)		0	0		0	(3,514)
Change in pension liability and postretirement obligations, net of tax	10,108		0	0		0	10,108
Stock compensation - directors	5,474	440	0	5,474	440	0	0
Stock Issued During Period, Value, Stock Options Exercised	441		2	439		0	0
Tax effect of exercise of stock options	(197)			(197)			0
Earned ESOP shares	47,306		23	47,283		0	0
Restricted stock units released, shares, net of shares withheld for minimum statutory tax obligation	(1,268)		0	(1,268)		0	0
closing balance at Mar. 31, 2017	341,350		226	258,853		179,735	(97,464)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	22,065		0	0		22,065	0
Payments of Dividends	(3,903)
Dividends declared			0	0		(3,903)	0
Change in foreign currency translation adjustment	21,717		0	0		0	21,717
Change in net unrealized gain on investments, net of tax	189		0	0		0	189
Change in derivatives qualifying as hedges, net of tax	3,563		0	0		0	3,563
Change in pension liability and postretirement obligations, net of tax	12,737		0	0		0	12,737
Stock compensation - directors	5,156	$ 430	0	5,156	$ 430	0	0
Stock Issued During Period, Value, Stock Options Exercised	6,332		4	6,328		0	0
Tax effect of exercise of stock options							0
Restricted stock units released, shares, net of shares withheld for minimum statutory tax obligation	(1,407)		0	(1,407)		0
closing balance at Mar. 31, 2018	$ 408,229		$ 230	$ 269,360		$ 197,897	$ (59,258)